The invention relates to fluid flow control and more particularly to flow rate control of diluent fluid to a locomotive diesel fuel emulsifier in increment steps as a result of positioning of the locomotive engine throttle.
It is well known that train locomotives utilize diesel combustion engines, either to directly drive locomotive axles and wheels or to drive main direct current generators which then supply electric power to a plurality of traction motors connected to the locomotive axles and wheels. Locomotive speed is controlled by means of a throttle handle movable in a specified number of steps with definite indexing of the steps to regulate fuel flow to the engine. It is often desirable, as a means for achieving a more stable and more efficient combustion process in the diesel engine, to provide for emulsification of the diesel fuel with a suitable diluent fluid, such as water, prior to combustion in the diesel engine. It is generally known that fuel emulsification results in higher combustion efficiency, thereby lowering the rate of fuel consumption, and minimizes unsightly smoke formation in the combustion exhaust gases. It is also believed that certain emulsification processes can lead to a reduction of noxious combustion emissions, especially sulfer oxides.
One known fuel emulsifier presently available for use in diesel locomotives is marketed by Fuel Control Systems, Inc., of Chicago, Ill. This emulsifier provides for a mixture of water with the diesel fuel prior to combustion. A single valve controls the delivery of water flow to the emulsifier, despite the various differing fuel flow rates being used to control the locomotive diesel. As a result, the optimization curve for the emulsifier is very narrow, limited to only one or two throttle positions. This tends to reduce the practicability of the emulsifier, since for most throttle positions the water mixture amount is either too low or too high to provide the desired stabilizing effect on the combustion process.
The present invention overcomes this drawback in emulsification operation by affording automatic means for selecting various desired flow rates of diluent fluid in accordance with the relative fuel flow rates and throttle positions at hand. The flow rate control system of the present invention is not limited to use with locomotive diesel emulsifiers and further and other objects of this invention will become apparent to those reading the detailed description and drawings which follow.